univention-apache is a service which should provide a nice default apache configuration for UCS. The ucs-overview with it's javascript/etc. has a different purpose and should therefor has it's own (source) package. The apache configuration for it also doesn't belong into the global configuration but into a configuration only for the ucs-overview.
*** This bug has been marked as a duplicate of bug 42233 ***
OK: this is obsolete by the new portal. ucs-overview has been removed.